Use field name containing dots as separator to look into object.

<div class="definition">
    Boolean, default = true
</div>

<textarea class="javascript">
let form = new w2form({
    name     : 'form',
    url      : 'server/post',
    header   : 'Field Types',
    record: {
        simple: {
            text: 'default text value',
            alpha: 'ABC123',
        },
        single: {
            check: true,
            toggle: true
        }
    },
    fields: [
        { field: 'simple.alpha', type: 'alphaNumeric',
            html: {
                label: 'Alpha Numeric',
                attr: 'style="width: 300px"'
            }
        },
        { field: 'simple.text', type: 'text',
            html: {
                label: 'Text',
                attr: 'style="width: 300px"'
            }
        },
        { field: 'single.check', type: 'checkbox',
            html: {
                label: 'Check box'
            }
        },
        { field: 'single.toggle', type: 'toggle',
            html: {
                label: 'Toggle'
            }
        }
    ],
    actions: {
        Reset() {
            this.clear();
        },
        Save() {
            this.save();
        }
    }
});
</textarea>